The present invention relates generally to the deposition of zinc oxide films. In one of its more particular aspects, this invention relates to zinc oxide films useful in photoconductive applications deposited by an improved chemical vapor deposition process.
In many applications where a zinc oxide film is deposited upon a heat-sensitive substrate, such as a photoconductive layer or layers, it is not desirable to deposit the zinc oxide at temperatures which may adversely affect the substrate. Although zinc oxide films have also been produced by chemical vapor deposition, such films have generally been produced only at high temperatures, for example, at temperatures of 350.degree. to 730.degree. C. In addition, films so produced have been characterized by relatively high resistivities.
It is accordingly an object of the present invention to provide a process for depositing a zinc oxide film at a relatively low temperature.
Another object of this invention is to provide such a process in which various additives can be conveniently added to the zinc oxide during deposition of the film to decrease the resistivity thereof.
Other objects and advantages of the present invention will become apparent from the following detailed description.